power



J. W. POWER.

SAFETY VALVE.

Patented oct. 13, 1885.

(No Model.)

UNITED STATES PATENT OFFICE.

JOHN W'. POWER, OF VES'I BAY CITY, MICHIGAN.

SAFETY-VALVE.

LEPECfT-IQZLAEON forming part of Letters Patent No. 328,062, dated October 13, 1885,

Application filed January 26, 1885. Serial No. 154,001.

To all whom t 19mg/ concern.-

Be it known that l, JOHN W. POWER, a citizen of the United States, residing at West Bay City, in the county of Bay and State of Michigan, have invented certain new and useful Improvements in Safety-Valves for Steam-Boilers; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this speciication.

Figure 1 is a sectional view of my improved safety-valve. Fig. 2 is a detached view of the same, showing spring attached in place of weight. Fig. 3 is a sectional view at x x in Fig. l.

Similar letters refer to similar parts throughout the several views.

My invention relates to improvements in safety-valves; and it consists, chiefiy, in the combination of certain parts and mechanism, as I hereinafter more fully describe and claim; and the object of my invention is to provide a means of allowing the surplus steam of a boiler to readily and easily escape, and to avoid cushioning the weighted valve upon the escaping steam, as is the effect in the valves in common use.

In the drawings, a represents the steamdome of the boiler, and c a chamber` properly attached to the top of the steam-dome. To the upper part of the chamber c is attached the cylinder b, provided at its lower end with the pipe d, which extends downward through the chamber c and to some distance into the steam-dome a.

Placed within the cylinder b is the piston e, provided with proper packing, if required to form a steam-tight joint around the same, and attached to this piston is the stem f, which extends upward to a suitable distance to conneet with the valve t', placed within a chamber, h, which is located directly above the cylinder I), and provided near its middle portion with the division j, having the valve-seat i', and forming a second chamber, 7L', below the division j. The chamber h is supported in position by the connecting pipe or steam- Way, g, which connects at the upper end with (No model.)

the chamber h, and at its lower end with the chamber c; and to the lower chamber, h', is attached an escape-pipe, K, for conducting away the surplus steam. The upper end of the chamber h is closed with a head, S, iirmly bolted to the chamber; and through this head, and extending downward to some distance into the chamber, is the adjustingscrew t, which serves to regulate the lift of the valve i from its seat and adjust the opening thereof for the escape of steam.

The steamway g is provided with a bracket, Z, to which is pivoted one end of the lever, m, which extends beyond the stem f, and is attached thereto by the link n, one end of l which is pivoted to the lever m, and the opposite upward-extending end is pivoted to the stem f. The outward-extendingarm of the lever f is provided with a movable weight, o, or a spring, p, as may be desired, for holding the lever m from being lifted by the pressure of steam below thepiston e until a given pressure is reached. The steam passes from the boiler into the chamber c, and through the steamwayg directly into the chamber h, and presses the valve t' irmly to its seat, and also passes through the pipe d into the cylinder b and acts upon the piston c, so that were the piston c and valve t' of the same area an equilibrium of pressure would be produced, and the valve would remain closed; but to overcome this equilibrium I make the area of the piston e considerably greater than that of the valve fi, and then adjust the weight o or spring p to overcome the difference in area, as well as to hold the desired pressure in the boiler. The pipe d extending below the entrance to the chamber c allows the steam to pass into the chamber and through the steamway g and open valve i without disturbing the pressure upon the piston e, so that when the pressure in the boiler is raised to a higher point than that to which it is designed to hold, the steam acting upon the piston e causes the piston to rise, together with the valve i, and allows the steam to escape beneath the said valve i until the excess of pressure is relieved, when the piston will return to its former position and seat the valve i.

I do not expect to use in all cases the valve fi, as herein shown and described, as a large variety of valves may be used in place there- IOO of, producing the same result, and some other form of valve may be desirable; but

What I claim as my invention, and desire to secure by Letters Patent, is-

l. In a safety-valve, the boiler or dome a, in combination with the chamber c, provided with a steamway, g, the cylinder b above the said chamber, and provided with a piston, e, and the steam -pipe d, having its upper end connected with the said cylinder, and its lower end extending into the boiler, substantially as shown and set forth.

2. In a safety-valve, the chamber c, having an opening to the boiler, the cylinder b above the chamber, and provided with the pipe d, the chamber h above and in alignment with the said cylinder b, and provided with the valve-seat z', and the steamway g, connecting the said chambers c and h, in combination with the valve t' and piston e, the stemf, connecting the said valve and piston, and the adjusting-screw t above the said valve t', substantially as and for the purpose set forth.

3. In a safety-valve, a steam-chamber having an opening to the boiler, a vertical cylinder secured tothe said chamber, and provided with a steam-pipe passing through the said chamber to the boiler, and a piston within the said cylinder, in combination with a valvechamber placed above and in alignment with the said cylinder, and provided With a valveseat and a valve of less area than the said piston, a stem connecting the said piston to the said valve, a lever for regulating the pressure within the boiler, a link connecting the said lever to the said stem, and a stearnway with one end connected with the said steamchamber, and with the opposite end connected with the valve-chamber above the valve therein, substantially as and for the purpose set forth.

4. In a safety-valve, the stem f, with one end connected with the piston e, and its opposite end connected with the valve i, and the lever m, provided with the weight 0, and with one end pivoted to the bracket Z, in combination with the link n, pivoted at one end to the lever m, and with its opposite end pivoted to the stemf, substantially as and for the purpose specified.

5. In a safety-valve, the cylinder b, provided with the pipe d and piston e, the chamber h. located above and in alignment with the said cylinder, and provided with the division j and valve t', and the stem f, in combination with the chamber c, located below the said cylinder, and the steamway g, having one end connected with the said chamber c, and its opposite end connected with the said chamber h above the valve t', substantially as set forth.

In testimony whereofI affix my signature in presence of two witnesses.

JOHN W. POI/VER.

Witnesses:

JOHN BRIGHAM, J r., SAMUEL L. BRIGHAM. 

